CXCL8 and Behcet disease: Furthermore, we found significant positive correlations between BD patients’ scores on the simplified Behçet ́s Disease Current Activity Form (BR-BDCAF), a validated tool to measure disease activity, and Streptococcus sanguinis-stimulated production of IL-23 by peripheral blood mononuclear cells (PBMC) and IL-8 by neutrophils.